It is known that a flight management system (FMS) can offer the crew of an aircraft assistance in the nominal execution of the descent and/or approach phases by constructing an optimized vertical profile.
In general, a vertical profile comprises an altitude profile and a speed profile. The construction of a vertical profile needs to meet various altitude and speed constraints devised and published by the authorities. Optimizing the vertical profile consists of applying a predefined strategy in the flight management system. Usually, the vertical profile is calculated using a known construction method and the values of a plurality of parameters.
During the descent and/or the approach, the crew flies the aircraft in such a way that it follows the vertical profile calculated by the flight management system. However, the crew has to execute the descent and approach operation while adhering to a great many constraints.
In particular, the crew has to adhere to various clearances issued by air traffic control, such as: clearance to start a descent; successive clearances to enter increasingly low altitudes or flight levels; maximum and/or minimum speed clearances; clearance to execute the approach; and clearance to land.
The clearances given by air traffic control may be more or less intrusive and may thus disrupt the ability to adhere to the vertical profile calculated by the flight management system.
Furthermore, the crew must also adapt to the actual conditions at the arrival airport in terms of actual air traffic, weather conditions, and operating constraints.
In the case of a commercial transport plane, the crew must generally execute the descent and approach operation while additionally conforming to a policy or strategy set by the airline.
Within a context in which optimizing the flight in terms of fuel consumption and flying time is becoming increasingly important, tying the aircraft to an optimized vertical profile would make it possible to conform to the airline's strategy while at the same time taking account of the environment in which the aircraft is flying, guaranteeing maximum savings (of fuel, time).
Currently, the single strategy for constructing the vertical profile that exists in a flight management system does not always make it possible to conform to the aforementioned wide range of requirements and constraints. Thus the vertical profile may be abandoned by the crew or considered merely as information that does not allow an optimal automated flight. It would therefore be desirable to provide an improved method and device for constructing a vertical profile for a descent and/or an approach of an aircraft,
In addition, other objects, desirable features and characteristics will become apparent from the subsequent summary and detailed description, and the appended claims, taken in conjunction with the accompanying drawings and this background.